well i have done alot of research on what oil and interval to use
everyone had diffrent opinions which is understandable but did not really
help me out
so......what do to,whos opinion to belive
so i asked my shop foreman who has been working with mercedes benz north america for 25 years (im a mercedes tech if you didnt know)
he explained it simply like this
the technology of engines and oil has changed drastically in the last 10 years
what additives go in the oil, what tempratures the oils can go through without moleculry braking down and the service interval they therefore can withstand
even with all these advancemants engine still go threw a brake in period which means small metal shaving being trapped in the engine and the engines
piston rings still requiring to be seated properly
if any one is familar with mercedes you would have known our heard of our engines having problems with oil consumption as a result of the rings not seating properly in the engines b/c of the material the cylinder walls are made from
and even in the advant of our new line of engines(E350,S550 etc)we still have this problem as the result of the use of syn oil
plain and simple it does not seat the piston rings very well to there surronding cylinder wall
he recommended changing oil and 2000 miles using regular mobile 5w30 no aditives just oil
next let the dealer perform there free service at 5000k with there regular oil which is also mobile no syn
next again change the oil one more time with regular oil letting the engine rings completely brake in all 6 cylinders
after that change to mobile 1 syn with a service interval of 5000 miles
syn oil gives the advantage of less friction in all the engine matting serfices
(cam gear to chain,cyl wall etc)therefore better gas milage and engine life
any one have any other suggestions ?
thanks in advanvce for your response
jon

 

yeah, except Valvoline Synpower. Just always used Valvoline.

 

Are you talking about Lexus or Mercedes? I'm a little lost here. Also, don't forget to use spell checker and throw in some periods and commas before posting next time.

Thanks Jon!

 

Lexus has revised their viscosity recommendation to 5W-20, which seems to be what was in my car from the factory. I posted my 5K used oil analysis report from Blackstone here.

 

I live in Australia and it's very hot here. Is it better to use 10W30 rather than 5W30. I would imagine 10W30 is more stable at high temperature. Castrol makes a full synthetic 10W30 oil.

 

I could see sticking with 5W-30 instead of 5W-20, but I would not consider 10W-30. The difference in ambient temperature can't be more than 20 degrees F, right? You might have more wear at startup by going with 10W-30.

 

Where did you find this revision from 5w30 to 5w20?

 

lobuxracer posted about the latest TSB on Toyota's tech site that specified 5W-20.

 

10w-30 synthetic is the most stable oil you can buy. It has no VI modifiers, so it doesn't suffer viscosity breakdown like so many other oils do. I've been using it for years with 10k mile change intervals and nothing but success in street driven engines.

 

Are you going to use 10W-30 in your IS instead of 5W-20?

 

I'll stick with the recommended oil simply because this is a new engine under warranty, and if there are any lubrication failures, I want Toyco to own solving them. If I choose to use something else, I would own any issues resulting from lubrication failure, even if it didn't appear to be related to viscosity. While Magnussen Moss is a wonderful thing, sometimes it works against you, especially when Toyco can afford very expert witnesses and I can't. I'd rather not void my warranty. It's also likely I'll get better gas mileage with lighter oil. I just need to do the same thing you did and send samples to Blackstone to determine my optimum change interval.

FWIW, I'm the guy who found out that Red Line D-4 ATF kills the DU bushings in the Getrag 233 in MkIV Supras. Another case of "recommended by lubricant manufacturer" but "not recommended" by the gearbox manufacturer causing serious issues. I owned fixing it, and it cost me $1800 in parts and two days of my "spare" time in the machine shop.

 

Does anyone have a link to this mysterious 5w20 TSB? I'm not terribly surprised, given that Toyco seem to run 5w20 in most of their engines, but I'm bewildered as to why they'd suddenly either decide to change their recommendation, or why it took them this long to realize they screwed up...

 

I think it is on TIS. I can't find anything through Google.

 

It's on TIS. TSB EG006-06. Posted here.

 

Don't you guys think SAE20 is a bit thin. I haven't seen much car uses such thin oil. Sure your engine rev faster but I'm really concern if it would be enough to protect the engine. Most European cars uses SAE 40 - 60.